public Task <Stream> TransformImage(Stream image, ImageDisParameters param)
{
var newImage = new MemoryStream();
using (var imageFactory = new ImageFactory(preserveExifData: false))
{
var chain = imageFactory.Load(image);
if (param.Has("w") || param.Has("h"))
{
var resizeLayer = new ResizeLayer(new Size(param.Get <int>("w"), param.Get <int>("h")));
resizeLayer.ResizeMode = ResizeMode.Max;
resizeLayer.AnchorPosition = AnchorPosition.Center;
if (param.Has("pad") && param.Get <bool>("pad"))
{
resizeLayer.ResizeMode = ResizeMode.Pad;
}
chain.Resize(resizeLayer);
}
chain.Save(newImage);
}
return(Task.FromResult <Stream>(newImage));
}
public IEnumerable <string> GetParameterAsParts(ImageDisParameters param)
{
if (param.Has("w") && param.Has("h"))
{
yield return(param.Get <int>("w") + "x" + param.Get <int>("h"));
}
else if (param.Has("w"))
{
yield return(param.Get <int>("w") + "w");
}
else if (param.Has("h"))
{
yield return(param.Get <int>("h") + "h");
}
if (param.Has("pad") && param.Get <bool>("pad"))
{
yield return("padded");
}
}
private async Task GetImage(HttpContext context)
{
// extract the key
var match = _getImageRegex.Match(context.Request.Path.ToString());
var key = match.Groups[1].Value;
// check if it even exists
if (!await _options.StorageProvider.CheckIfKeyExists(key))
{
context.Response.NotFound();
return;
}
// parse the params
var param = new ImageDisParameters().AppendParameters(context.Request.Query);
var parts = _options.ImageTransformProvider.GetParameterAsParts(param);
// check if the new key exists (or if no param parts were added to the end, the original)
var newKey = key;
if (parts.Any())
{
newKey = newKey + "_" + string.Join("_", parts);
}
if (newKey == key || await _options.StorageProvider.CheckIfKeyExists(newKey))
{
context.Response.Redirect(await _options.StorageProvider.GetRedirectPath(newKey));
return;
}
// apply transformations, save to storage and redirect user
var original = await _options.StorageProvider.GetFile(key, _options);
var newFile = await _options.ImageTransformProvider.TransformImage(original.Stream, param);
await _options.StorageProvider.SaveFile(newKey, original.ContentType, newFile, _options);
context.Response.Redirect(await _options.StorageProvider.GetRedirectPath(newKey));
}
public static ImageDisParameters AppendParameters(this ImageDisParameters param, IReadableStringCollection query)
{
foreach (var q in query)
{
int integer;
bool boolean;
if (int.TryParse(q.Value.First(), out integer))
{
param.Add(q.Key, integer);
}
else if (bool.TryParse(q.Value.First(), out boolean))
{
param.Add(q.Key, boolean);
}
else
{
param.Add(q.Key, q.Value.First());
}
}
return(param);
}
